Ringing-tone circuits



F. M. SLOUGH.

RINGING TONE CIRCUITS.

APPLICATION FILED DEC. 1. 1916.

Patented Sept. 28, 1920,

UNITED, STATE S PATENT OFFICE.

FRANK M. SLOUGH, or ROCHESTER, NEW YORK, As-sIeNon. To THE. STROMBERG- I CARLSQN TELEPHONE MANUFACTURING coiv'rnNy, or ROCHESTER, NEW

YORK, A CORPORATIO on NEW YoRK; l 1

RINGING-TONE. clnourrs.

Specification of LettersPatent. Patented Se t 1920.

Application filed. December 1, 1816. Serial No. 134,227. 7 j

To all whom it may concern:

Be it known that I, FRANK M. Snoueii,

and useful Improvements in Ringing-Tone Circuits, of which the following isa full,

clear, concise, and exactde'scription', reference being had to the accompanying'drawings, forming a part of this specification. Ithas beenproposed in improved telephone systems to so arrange. the central office apparatus that. the subscriber shall hear in'his telephone receiver, the sound of a ringing bell; this for the purpose of reassuring the callin subscriber that the call is being sent to the telephone of the called subscriber in the proper manner and that the called subscribers bell is ringing. It has been proposed to do this by arranging a ringing bell and a telephone transmitter in close proximity one to vthe other, the

transmitter circuit being arranged to in clude a sourceof current and the necessary conducting wires, coils, etc., which are usual in telephonic transmitting circuits. 7

'It has been further proposed to arrange the above apparatus in thecentral oi'lice Where connections are completed by the act ofa telephone operator, or by automatic means. Means have also been proposed for connecting to the line of the calling subscriber the tone transmitting circuit, so that the tone producedby the ringingbell may be projected over the line of the calling subscriber and heard in the receiver of the call ing line telephone. Y

However, the above arrangement has been far fromsatisfactory, .due to the fact that the transmitter transmits not only the sound of the ringing bell but also the pounding sound which is-produced by the impact of the bell tapper upon the bell gong, consequently the sound received by'the calling. subscriber is not the clear, ringing tone of the bell, but rather largely a confused poundingnoise produced by the impact of the gong trapper upon the gong. It has been found that in all arrangements of the kind proposed that the pounding sound predominates' and that Very little of the ringing tone can be heard above the sound produced by the impact.

It is particularly the object of this invention to produce a tone device which will permitv the clear, ringing tone of the bell without the tone being obscured in any way by the sound of the-impact of the tapper upon the gong.

I have shown: anrembodiment of my invention in the accompanying drawing, in which Figure l is a plan view of a bell constructed in accordance with my invention; Fig. 2 is a circuit diagram of an em bodiment of my invention as applied to a manual telephone system. Fig. 3 is a circuit diagram of an embodiment of my invention as applied to a manual telephone system in which the ringing is intermittently applied by an electromagnetic key.

In the drawings G represents a gong at the central ofiice which is caused to sound by the impact of a tapper t, the same being mounted upon an armature a, which is caused to vibrate by virtue of the intermittent attraction of the magnet coils m, as controlled by the controlling contacts 0. The energizing circuit of this bell is that of the ordinary and welllrnown vibrating bell, and contains a source of current E, and needs no detailed description, being wel linown in the art. The well-known closed circuit form of hell is shown in Fig. 1, and this type of closed circuit bell being indicated at C. A magneto bell operated by alternating current could obviously be employed.

Referring to the figures, I show an extra set of contacts as composed of a spring S and associated spring 0 the two contacts of the springs being so adapted to make an electrical connection when the tapper is at that part of its strokedistant from the gong, and which is adapted to break this electrical contact when the tapper is striking the gong. At T I' show a telephone transmitter which'may be ofany of the well-known types. Thistransmitter is arranged in close proximity to the vibrating or soimding gong G. This transmitter may be merely a transmitter button whose electrode, which is ing s, impedance coils Z and a source of cur-' rent E The electrical contacts between the spring S and the contact are hereshown V in that part of the transmitting circuit which leads to the primary winding 79 of the 1nduction coilz'. Condensers 7c, are connected in the circuit of the secondary winding 8 and in the wires (w and .w which leadto the telephone switchboard. Terminal binding posts 6 and b, are shown at the point where the various taps are made from various switchboard connecting'circuits to the'fcommon tone transmitting circuit C just discussed. At O I show an operators switchboard connecting circu1t,'wh1ch""1s here shown connecting a telephone sub-station at i A to a telephone sub-station at B. The

connection is here shown as being made by 7 means of plug and jack switches shown at J and J At the station A the "subscribers apparatus is shown in a connected position, the switch-hook contacts it connect- 7 ing the receiving apparatus to the line wires being-closed, and at" Bthe telephone apparatus is shown in its retired position, wlth the switch-hook contacts k open, and the sub-station bellat B connected across the line,'and' asthe circuits are shown in'Fig. 2, the bell Z) is being operated by current from a ringing generator D-at the central oflice. V The sub-stat on apparatus at stations A I and B is well-known inthe art and will not be described here. The operators connective apparatus is likewise well known in the art and will therefore not be described,

with the-exception of the ringing key K, WillCh' is here shown in its operated or ringing position; the contacts '1" serving to con.

met the ringing generator D to the called telephone line upon which is located the called -sub-station]3. The ringing keyK also consists of two pairs of contacts 7",

' ceiver R.

which serve at thesame time to connect the ringing tone transmitting circuit C to the connecting circuit 'conductorsl and 2 leading back to the calhng' sub-station re- The vibrating bell being means of its energizlng circuit, including the source ofcurrent E, its magnetsm and l its controlling contacts a, it is" apparent that thegong G 'will be struck rapidly and thus be kept in a continual state of vibration,

producing a ringing tone. The transmitter- T is arranged in close proximity'to the gong G and its diaphragm (not shown) will be 7' source of current E through the impedance coils Z and the conducting wires 3 and 4, leading to the transmitter T. At the points 5 and 6 a circuit is arranged in multiple scribed, it beingunderstood that the current operated The 'ing as used in the art.

with thetransmitter T as follows: From known manner vary the transmitter resistance; the transmitter being I connected in multiple with the circuit just described will therefore likewise vary the electrical potential existing at the points 5 andv 6, and thereforecauseia vibrating current to flow through this circuit corresponding to the vibrations'of the transmitter diaphragm. It has been found that the bell tapper when striking the gong, remains incontact with it long'enough to interfere Iwith its free or undampedj vibration,rand at this j time 'pro- 7 duces adull thudding sound, followed, when the tapperleaves the gong, by a new and accelerated train-of free vibrations; Atthe moment before, and while the gong G is struck by thetapper t, the circuit'of the primary coil 17 will be broken at the contacts S and c consequently the tone current or Vibrating current willnot flow at this time through the said primary "winding, and the pounding sound' of impact caused-by the tapper striking, and thus momentarily dampingthe .free vibrationof the gong, will not. be transmitted back to the calling subscriben' However, the gong will continue to vibrate afterbeing struck'until thecontactsjS are again closed, the tapper at this time being at that part of its stroke distant from thejgong, and rat thistime the characteristic sound due to free vibration of the gong will'be heard by the calling subscriber at A over the circuit which has been depulsations in the primary winding are reproduced in the secondarywindings in the well-lmownmanner, and such pulsations of currentcorresponding to the sound of the clear ringing bell will therebybe caused to flow over the circuit leading to thecalling subscribers receiver B, through the condensers 70 and over the wires to and w the contacts r of the key K, the connecting circuit contacts 1 and 2, line wires 9 and 10, and thence through the switch-hookfcontacts h at the sub-station A to the receiver R of the calling subscriber. I

At Fig. 3: I show a portion of such a connective circuit" as 0 except that in the con- 1 20 nective circuit of Fig. '3 the ringing is 'accomplished 'in an intermittent manner and 'the intermittent ringing current is applied to the called subscribers line by means of an electromagnetic key 70 after an initial depression of a manually operated key K '7 So far this operation does not differ from the method ot'automatic interrupted ring- I In addition,Iprovide the contact s'pringsr, which in a manner causing its vibration.

analogous to that just described for the manually operated key K of connective circuitO operate to connect the ringing tone current to the conductors 1 and 2 leading back to the calling subscribers telephone. I provide in additiomin the common tone supply leads @12 and cos interrupters e, which may rotatein synchronism with interrupter, g. In this way means are -provided to transmit back to the-calling subscriber an interruptedringing tone which may correspond to the interrupted ringing of the called subscribers telephone -bell. In F 3 the electromagnetic key k and the manually operated key K are both'shown in their unoperated position. Means are provided consisting of the trip relay 1 1 having contacts arranged so as to shortcircuit the relay k upon the response of the called'subscriber. By arranging the tone transmitting circuit through the contacts a, during the ringing period, I place the connection of the characteristic ringing tone circuit to the calling subscribers telephone v the same can be made without departing from the spirit of the invention, such as arranging a mechanical gong striking device and a mechanical contact making device,

which could be arranged so that the contact of the tone producing circuit would be closed after the gong receives the impulse Such an impulse may be given by impact or any other way, such as electromagnetic attractions or repulsions upon a gong, which may be mad in such a case of steel.

l Vhat I claim as new and desire to secure, v

by Letters Patent is V 1. In a telephonic tone device, a vibratile member, means for actuating said member, a

telephone transmitter arranged in proximity thereto, a transmitting circuit for said transmitter, a telephone receiving circuit 2. In a telephone system, the combination of a transmitter, a circuit therefor, a telephone receiving circuit, a vibratile soundtapper,

ing member," striking means i'orsaid sounding member to cause-said sounding member to sounda signal fora period of time, and periodic automaticdisabling means" to disable the said transmitter circuit for a first portion of the said periodof time.

- In atelephonic tone device, a'gong, a tapper for said gong, a telephone transmitter,- a circuit therefor, and automatic periodic means for disabling said transmitter circuit whenever said gong is; struckby said tapper.

4. In a telephonic tone device, a gong,a

tapper for saidgoing', a telephone transmitter, a circuit therefor, a telephone receiving circuit, meansifor connecting said transmitter and receiving circuits, and automatic periodic means for disabling said transmitterv circult when. said "gong 1S struck by said -5L-In a telephonic tone device, a vibratile member, means'ioractuating said member, a micro -phone, a transmitting circuit therefor, a telephone receiving circuit, electromagnetic means to connect said telephonic transmitting: circuit tosaid receiving circuit, and automatic periodic disabling -means to disable said transmitting circuit at the time of actuation member. s c a 6. The method of producing ringingtone of said vibratile currents consisting in causing a vibratile body to mechanically vibrate in a train of vibrations consisting of forced or damped vibrations and free vibrations, and translating only the free mechanical vibrations into corresponding electrical pulsations.

Z. In a telephone system a calling and a called subscribers line terminating in line jacks at a central oilice, a link circuit for connecting said lines in conversation, a source of ringing current associated with said link circuit and adapted to be impressed upon the line of said called sub- 'scriber, a tone signal member, means to actuate said member, means for converting the tone produced bysaid signaling member into current impulses of corresponding characteristics impressed upon said calling subscribers line when said ringing current is impressed upon said called subscribers line and automatically operated disabling means for said converting means at the time of actuation of said tone signal member.

8. A telephone system, a callingand a called subscribers line terminating in line jacks at a central oflice, a link circuit for connecting such lines in conversation, a source of ringing current associated with said link circuit and adapted to be impressed upon the line of said called subscriber, a signaling device and actuating member, means to cause said member to actuate said signaling device, a telephonic element associated with saidsignaling device, periodic disabling means for said telephonic element, means for inductively connecting said; telephonic element. with the talking strands of said link circuit and a controlling circuit changing member associated with last named connecting means whereby the calling subscriber is given a characteristic undamped tone whenever said ringing current is applied to said line. 9. In a telephone system a calling and a called subscribers line terminating in line jacks at a central oiiice, a link circuit for connecting said lines in conversation, ,a sourceor ringing current associated with said link circuit and adapted to b61211.- pressed upon the line for said called subscriber, a ringer, a tapper for said ringer, meanszto cause said tapper to actuate said ringer, a telephonic element associated with said ringer, means for inductively connecti-ng said telephonic elementivith the talking strand of said link circuit, an apparatus associated With said ringer whereby the calling subscriber is given the sound of a bell ringing unmodified by the damping effect produced upon said bell by saidtapper.

10. In a telephone system subscribers line terminating at a central ofiice, a link circuit having one end connected with one of said lines, a source ofringing current,

rmeansto connect saidjsource of tonesig- :nahng current to the other end of said link circuit. v

11. The method of producing ringing tone currents consistin of a 'itatin a vibratile i h b D body by an initial impulse causing the same to vibrate first in a forced manner and subsequently in a free manner, ,andtranslating only the tree mechanical vibrations into corresponding electrical pulsations.

12. The method of producing a signaling tone current consisting of intermittently agitating a vibratile body causing successive mechanical trains of, forced and free vibrations, and then translating only the portion of each train which consists of free mechanical vibrations, into corresponding electrical pulsations.

In witness whereof, I hereunto subscribe my name this 28th day of November, A. D.

FRANK M. SLOUGH. 

